16.8 A/600 V AlGaN/GaN MIS‐HEMTs employing LPCVD‐Si 3 N 4 as gate insulator

Abstract

An AlGaN/GaN metal-insulator-semiconductor high electron mobility transistor (MIS-HEMT) on Si substrate was obtained with 18 nm silicon nitride (Si3N4) grown by low-pressure chemical vapour deposition (LPCVD) as the gate insulator. The D-mode MIS-HEMT shows a high I-dss of 16.8 A at V-g = 3 V, a high breakdown voltage (BV) of 600 V and a low-specific on-resistance of 2.3 m Omega.cm(2). The power device figure of merit (FOM = BV2/R-on,R-sp) is calculated as 157 MW.cm(-2). The good insulation effects of LPCVD-Si3N4 were also demonstrated by the low gate leakage current of 154 nA at V-ds = 600 V and V-gs = -14 V. Furthermore, an E-mode device was realised by a low-voltage silicon metal-oxide-semiconductor field-effect transistor in series; the V-th was determined to be 2.6 V. The high I-dss, low-specific on-resistance, high BV and positive V-th show the potential and advantages of GaN MIS-HEMTs for power switching applications.